Together, Kristen Anderson-Lopez and her husband Bobby Lopez wrote the music for Disney’s megahit “Frozen,” but they were celebrating separately Thursday when they received an Oscar nomination for the song “Let It Go.” After leaving Sunday’s Golden Globes without an award, Bobby stayed on in L.A., while Kristen returned to their Brooklyn home and their daughters, ages 4 and 8 (whose voices can be heard in the film). This morning Kristen dropped them off at school, and then dashed home just in time to see their category announced. “I think I woke him up on the other coast with my screaming,” she said in a phone interview.

Singer Idina Menzel’s soaring, defiant rendition of “Let It Go” has defined the success of the animated film about a princess, Anna (Kristen Bell), questing to find her older sister, Elsa (Menzel), who has plunged their kingdom into unending winter. The first soundtrack to an animated Disney film to hit No. 1 since 1995, “Frozen” is currently at the top of the albums chart for a second week. And the Web has been overrun with videos of kids and grown-ups alike singing their own versions of “Let It Go.” (Kristen said her latest favorite is a medley by members of the vocal group Pentatonix.)

“As a musical theater composer, you train yourself not to expect this kind of success, so it’s always a little bit bewildering if you get it,” Bobby said by phone, as he drove through L.A.

“Frozen” also received a nomination for best animated film. With $714 million at the worldwide box office so far, “Frozen” is Disney’s highest-grossing film of all time. In a separate phone interview, directors Chris Buck and Jennifer Lee said they’re still reeling from the film’s success. “I felt like we were taking a few risks, going out with a big, bold musical and two female leads and a sincere fairytale. We didn’t know if people would come,” said Lee, who watched the Oscar nominations on her laptop while in bed with the flu.

Next week, the directors travel to Japan to help open the film there. After the Oscars in March (and a break), by summer the filmmakers expect to start adapting “Frozen” for Broadway, an effort Disney chief Bob Iger recently announced. Disney “would like us to be as involved as we can,” said Lee, adding that the Lopezes are also expected to participate. Considering their theater experience, including Bobby’s work on “The Book of Mormon” and “Avenue Q,” Lee said, “They’re beautifully qualified to do that. We all know the characters better than anyone.”

Buck added, “There are quite a few songs they could dust off that didn’t make it into the movie, at least the melodies.”

As for the Oscars ceremony itself, the songwriters said it’s too early to know how “Let It Go” might be performed. “It’s not in our control, but we do hope that everyone gets to see the amazing Idina Menzel sing,” Kristen said. The song was also released as a single recorded by singer Demi Lovato. Lee said she came to enjoy Lovato’s version as a “power anthem with a little angst in it,” but added, “For us, Idina is Elsa.”

The acclaim around the soundtrack helps revive the musical legacy of Disney, established by such songwriters as Howard Ashman and Alan Menken, the team behind “Aladdin,” “Beauty and the Beast” and “The Little Mermaid.”

Working closely with other “Frozen” creators, the Lopezes strived to capture a traditional Disney sound, while adding contemporary twists. Among the lyrics in “Let It Go” that bear a 21st century stamp, Bobby said, is the line, “The cold never bothered me much anyway.” Bobby describes it as “a very subversive lyric that helps the charisma of the character.”

For Kristen, the lyric “be the good girl you always have to be” resonated personally. She said, “As a female writer I brought a lot of myself to the song, and how hard you have to work not to worry about what people think and whether you’re living up to their expectations of a wife and a mother. You literally have to take those thoughts and slam the door on them.”

After the duo came up with “Let It Go,” the script was essentially rewritten around the number, the directors said. “The song blew us away. It told a much grander story of Elsa. We were dealing with her as a villain up until that moment. That song set us free to do something different,” Lee said.

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